Return std::result

[SetOfAllSets]

Instead of returning an empty value on unsupported systems an err could be returned.

[GuillaumeGomez]

There is a const to check that. It would make the whole API more annoying otherwise, don't you think?

[SetOfAllSets]

I think it would make the api safer. Checking whether a string is empty to say the system is unsupported should be done in most cases and making it return an std::result would make users of the library think about that.

[GuillaumeGomez]

This would just increase complexity of the API for an information that you can check with a constant. Doesn't sound like a good idea...

[SetOfAllSets]

This would just increase complexity of the API for an information that you can check with a constant. Doesn't sound like a good idea...

While with a perfect programmer this would be correct, we live in a world with imperfect actors. Rust code and libraries should nudge users towards proper and safe code and I believe this change would do that.